TiSr antisite: An abundant point defect in SrTiO3

Abstract

We present a systematic study of the positron lifetime as a function of measurement temperature in strontium titanate (SrTiO3) single crystals grown in different conditions and by different synthesis methods. We combine our experimental results with state-of-the-art theoretical calculations of positron annihilation parameters. We find that the essentially omnipresent 180–190 ps lifetime component is most likely the TiSr antisite defect, possibly coupled with one or more oxygen vacancies, supporting the importance of the TiSr antisite related defects in SrTiO3.